(a) Field of the Invention
This invention pertains to a metal sailboat mast assembly and a method of fabrication.
(b) Description of the Prior Art
Sailboat metal masts of the prior art typically are constructed of a combination of extruded metal sections that are fastened together by rivets or welded together to form the completed mast for the sailboat. U.S. Pat. No. 2,519,230 depicts such a mast constructed of two extruded sections that are riveted together.
A different method for joining the sections together is disclosed in U.S. Pat. No. 4,072,121. The "121" patent uses "C" shaped joining strips which fit over flanges located at the edges of the extruded sections to hold the mast sections together. In operation, however, the joining strips tend to slide up or down the mast and allow the mast sections to move relative to each other thus weakening the structural integrity of the mast.
U.S. Pat. No. 4,211,179 discloses the use of an "H" shaped or a dumb-bell shaped plastic extrusion for joining mast sections together. This construction also suffers from problems associated with the sliding of the mast sections relative to each other.